how to use VI editor

Another way to save your changes and exit out of VI is the ZZ command. When in command mode, type ZZ and it will do the equivalent of :wq. If any changes were made to the file, it will be saved. This is the easiest way to leave the editor, with only two keystrokes.

The Two Modes of VI

The first thing most users learn about the VI editor is that it has two modes: command and insert. The command mode allows the entry of commands to manipulate text. These commands are usually one or two characters long, and can be entered with few keystrokes. The insert mode puts anything typed on the keyboard into the current file.

VI starts out in command mode. There are several commands that put the VI editor into insert mode. The most commonly used commands to get into insert mode are a and i. These two commands are described below. Once you are in insert mode, you get out of it by hitting the escape key. If your terminal does not have an escape key, ^[ should work (control-[). You can hit escape two times in a row and VI would definitely be in command mode. Hitting escape while you are already in command mode doesn't take the editor out of command mode. It may beep to tell you that you are already in that mode.

How to Type Commands in Command Mode

The command mode commands are normally in this format: (Optional arguments are given in the brackets)

[count] command [where]

The count is entered as a number beginning with any character from 1 to 9. For example, the x command deletes a character under the cursor. If you type 23x while in command mode, it will delete 23 characters.

Some commands use an optional where parameter, where you can specify how many lines or how much of the document the command affects, the where parameter can also be any command that moves the cursor.

Some Simple VI Commands

Here is a simple set of commands to get a beginning VI user started. There are many other convenient commands, which will be discussed in later sections.

a

enter insert mode, the characters typed in will be inserted after the current cursor position. If you specify a count, all the text that had been inserted will be repeated that many times.

h

move the cursor to the left one character position.

i

enter insert mode, the characters typed in will be inserted before the current cursor position. If you specify a count, all the text that had been inserted will be repeated that many times.

j

move the cursor down one line.

k

move the cursor up one line.

l

move the cursor to the right one character position.

r

replace one character under the cursor. Specify count to replace a number of characters

u

undo the last change to the file. Typing u again will re-do the change.

x

delete character under the cursor. Count specifies how many characters to delete. The characters will be deleted after the cursor.

Text Buffers in VI

The VI editor has 36 buffers for storing pieces of text, and also a general purpose buffer. Any time a block of text is deleted or yanked from the file, it gets placed into the general purpose buffer. Most users of VI rarely use the other buffers, and can get along without the other buffers. The block of text is also stored in another buffer as well, if it is specified. The buffer is specified using the